On the edge of the Arabian peninsula, where the desert meets the Gulf, an architect and a chemical engineer are trying to sell sand. This is not normal sand, however; this is taken from Saudi Arabia, roughened up in a lab and sold for use in concrete.

Towering above us in Dubai is the world’s tallest building, the 163-storey Burj Khalifa. The concrete in the soaring structure was made of sand imported from Australia, said Jorge Gascon, a professor of chemical engineering. “Using local sand allows us to reduce carbon emissions by close to 60 per cent.”

Unrefined desert sand is simply not right for making concrete. The construction industry requires “sharp sand” taken from rivers or beaches — the desert variety is too smooth. But Gascon, working with the architect William McDonough, has worked out how to sharpen desert sand so that it can be used for buildings.

Their company, ClimateCrete, is being launched at the Cop28 UN climate conference in Dubai, and they are looking for customers. They are not alone.